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Front Cover
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Semantic Web for the Working Ontologist Modeling in RDF, RDFS and OWL
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Copyright Page
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Contents
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Preface
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About the Authors
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Chapter 1: What Is the Semantic Web?
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What Is a Web?
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Smart Web, Dumb Web
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Smart Web Applications
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A Connected Web Is a Smarter Web
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Semantic Data
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A Distributed Web of Data
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Features of a Semantic Web
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What about the Round-Worlders?
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To Each Their Own
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There's Always One More
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Summary
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Fundamental Concepts
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Chapter 2: Semantic Modeling
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Modeling for Human Communication
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Explanation and Prediction
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Mediating Variability
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Variation and Classes
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Variation and Layers
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Expressivity in Modeling
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Summary
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Fundamental Concepts
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Chapter 3: RDF-The Basis of the Semantic Web
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Distributing Data Across the Web
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Merging Data from Multiple Sources
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Namespaces, URIs, and Identity
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Expressing URIs in Print
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Standard Namespaces
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Identifiers in the RDF Namespace
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Challenge: RDF and Tabular Data
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Higher-Order Relationships
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Alternatives for Serialization
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N-Triples
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Notation 3 RDF (N3)
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RDF/XML
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Blank Nodes
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Ordered Information in RDF
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Summary
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Fundamental Concepts
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Chapter 4: Semantic Web Application Architecture
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RDF Parser/Serializer
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Other Data Sources-Converters and Scrapers
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RDF Store
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RDF Data Standards and Interoperability of RDF Stores
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RDF Query Engines and SPARQL
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Comparison to Relational Queries
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Application Code
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RDF-Backed Web Portals
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Data Federation
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Summary
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Fundamental Concepts
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Chapter 5: RDF and Inferencing
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Inference in the Semantic Web
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Virtues of Inference-Based Semantics
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Where Are the Smarts?
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Asserted Triples versus Inferred Triples
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When Does Inferencing Happen?
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Inferencing as Glue
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Summary
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Fundamental Concepts
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Chapter 6: RDF Schema
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Schema Languages and their Functions
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What Does it Mean? Semantics as Inference
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The RDF Schema Language
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Relationship Propagation through rdfs:subPropertyOf
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Typing Data by Usage-rdfs:domain and rdfs:range
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Combination of Domain and Range with rdfs:subClassOf
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RDFS Modeling Combinations and Patterns
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Set Intersection
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Property Intersection
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Set Union
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Property Union
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Property Transfer
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Challenges
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Term Reconciliation
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Instance-Level Data Integration
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Readable Labels with rdfs:label
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Data Typing Based on Use
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Filtering Undefined Data
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RDFS and Knowledge Discovery
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Modeling with Domains and Ranges
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Multiple Domains/Ranges
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Nonmodeling Properties in RDFS
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Cross-Referencing Files: rdfs:seeAlso
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Organizing Vocabularies: rdfs:isDefinedBy
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Model Documentation: rdfs:comment
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Summary
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Fundamental Concepts
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Chapter 7: RDFS-Plus
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Inverse
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Challenge: Integrating Data that Do Not Want to Be Integrated
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Challenge: Using the Modeling Language to Extend the Modeling Language
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Challenge: The Marriage of Shakespeare
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Symmetric Properties
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Using OWL to Extend OWL
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Transitivity
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Challenge: Relating Parents to Ancestors
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Challenge: Layers of Relationships
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Managing Networks of Dependencies
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Equivalence
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Equivalent Classes
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Equivalent Properties
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Same Individuals
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Challenge: Merging Data from Different Databases
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Computing Sameness-Functional Properties
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Functional Properties
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Inverse Functional Properties
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Combining Functional and Inverse Functional Properties
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A Few More Constructs
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Summary
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Fundamental Concepts
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Chapter 8: Using RDFS-Plus in the Wild
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SKOS
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Semantic Relations in SKOS
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Meaning of Semantic Relations
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Special Purpose Inference
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Published Subject Indicators
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SKOS in Action
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FOAF
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People and Agents
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Names in FOAF
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Nicknames and Online Names
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Online Persona
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Groups of People
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Things People Make and Do
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Identity in FOAF
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It's Not What You Know, It's Who You Know
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Summary
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Fundamental Concepts
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Chapter 9: Basic OWL
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Restrictions
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Example: Questions and Answers
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Adding "Restrictions"
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Kinds of Restrictions
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Challenge Problems
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Challenge: Local Restriction of Ranges
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Challenge: Filtering Data Based on Explicit Type
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Challenge: Relationship Transfer in SKOS
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Relationship Transfer in FOAF
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Alternative Descriptions of Restrictions
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Summary
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Fundamental Concepts
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Chapter 10: Counting and Sets in OWL
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Unions and Intersections
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Closing the World
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Enumerating Sets with owl:oneOf
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Differentiating Individuals with owl:differentFrom
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Differentiating Multiple Individuals
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Cardinality
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Small Cardinality Limits
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Set Complement
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Disjoint Sets
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Prerequisites Revisited
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No Prerequisites
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Counting Prerequisites
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Guarantees of Existence
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Contradictions
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Unsatisfiable Classes
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Propagation of Unsatisfiable Classes
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Inferring Class Relationships
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Reasoning with Individuals and with Classes
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Summary
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Fundamental Concepts
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Chapter 11: Using OWL in the Wild
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The Federal Enterprise Architecture Reference Model Ontology
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Reference Models and Composability
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Resolving Ambiguity in the Model: Sets Versus Individuals
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Constraints Between Models
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OWL and Composition
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owl:Ontology
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owl:imports
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Advantages of the Modeling Approach
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The National Cancer Institute Ontology
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Requirements of the NCI Ontology
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Upper-Level Classes
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Describing Classes in the NCI Ontology
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Instance-Level Inferencing in the NCI Ontology
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Summary
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Fundamental Concepts
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Chapter 12: Good and Bad Modeling Practices
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Getting Started
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Know What You Want
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Inference Is Key
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Modeling for Reuse
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Insightful Names Versus Wishful Names
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Keeping Track of Classes and Individuals
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Model Testing
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Common Modeling Errors
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Rampant Classism (Antipattern)
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Exclusivity (Antipattern)
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Objectification (Antipattern)
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Managing Identifiers for Classes (Antipattern)
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Creeping Conceptualization (Antipattern)
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Summary
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Fundamental Concepts
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Chapter 13: OWL Levels and Logic
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OWL Full versus OWL DL
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Provable Models
Provable Models
Class/Individual Separation
317
InverseFunctional Datatypes
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OWL Lite
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Other Subsets of OWL
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Beyond OWL 1.0
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Metamodeling
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Multipart Properties
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Qualified Cardinality
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Multiple Inverse Functional Properties
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Rules
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Summary
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Fundamental Concepts
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Chapter 14: Conclusions
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Appendix: Frequently Asked Questions
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Further Reading
336
Index
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